Katie Holmes is said to be increasingly worried about her movements being followed by Scientologists which apparently began before she split from Tom Cruise, 49.

The actress announced last week that she was divorcing the Hollywood star after five years of marriage and wants sole custody of their six-year-old daughter Suri.

Britain's The Sun newspaper reports that Katie, 33, was being followed by mystery men days before she filed to end her high-profile marriage.

"About three days before the divorce was announced a Mercedes SUV was sitting outside Tom's apartment in Greenwich Village," a source told the publication.

"They were sat about a hundred yards from the house a couple of suspicious looking characters in sunglasses. When Katie came out they tried to discreetly follow her. It was obvious they weren't paparazzi or Press.

"Then when it emerged Katie has rented a new place in the Chelsea area they were watching that too."

Katie apparently was spooked by the "spies" and asked her security personnel to take pictures of them and call the police.

The insider added that Katie "just wants the best for Suri. This is awful for her but she is being very brave. It's a terrifying situation for Katie."

Scientology's legal rep told TMZ that they are not following Katie.